Rigid consumable foam powder bag

ABSTRACT

A powder bag for gun propellant charges in the form of a hollow cylindrical casing and made from high density polyurethane foam. The cylinder is filled with propellant and closed at both ends by consumable cloth caps, one cap having a standard ignition pad attached externally thereto. A cloth handling strap may be attached to the second cap and gun bore erosion reduction additives may be impregnated in the foam casing.

United States Patent [191 Ayer RIGID CONSUMABLE FOAM POWDER BAG [75]Inventor: Douglas E. Ayer, La Plata, Md.

[73] Assignee: The United States of America as represented by theSecretary of the Navy, Washington, DC.

22 Filed: Apr. 26, 1972 [21] Appl. No.: 247,541

[52] US. Cl. 102/97, 102/24 R, 102/43 P, 102/DIG. 8 [51] Int. Cl. F42b9/24 [58] Field 01 Search 102/97, 38, 43 R, 102/43 P, 46, 24 R [56]References Cited UNITED STATES PATENTS 1,625,631 4/1927 Spotswood et a1102/97 3,257,948 6/1966 Axelrod et a1 102/43 P Nov. 13, 1973 3,397,6368/1968 Jacobson et al. 102/38 2,405,104 7/1946 Mydans 102/97 1,329,5032/1920 Casey 102/97 2,748,701 6/1956 Barrows 102/43 P PrimaryExaminer-Robert F. Stahl Attorney-R. S. Sciascia et al.

[57] ABSTRACT A powder bag for gun propellant charges in the form of ahollow cylindrical casing and made from high density polyurethane foam.The cylinder is filled with propellant and closed at both ends byconsumable cloth caps, one cap having a standard ignition pad attachedexternally thereto. A cloth handling strap may be attached to the secondcap and gun bore erosion reduction additives may be impregnated in thefoam casing.

6 Claims, 1 Drawing Figure RIGID CONSUMABLE FOAM POWDER BAG BACKGROUNDOF THE INVENTION This invention relates generally to ordnance propellantcharges, and more particularly, to powder bags having more durabilitythan conventional cloth bags. The need for improved powder bags becomesevident where one realizes that the standard cloth propellant bag hasbeen employed by the Army and Navy, with virtually no design changes,since the early 1900's. The standard cloth bag has a specific electricalresistivity permitting electrostatic charges to be built up creating aserious hazard of explosion and is incompatable with some propellants.It is difficult to fabricate, requiring hand sewing, and often stretchesout of shape hindering gun loading. Furthermore, the use of cloth allowsrips, tears, and holes to develop during handling, and most cloth issusceptible to rot and other biological degradation. Despite theseserious problems, no significant design changes have been made to thisbag. Various fabrics and cloth have been used as well as metal cartridgecases being substituted in some cases, but they have not substantiallyimproved the powder bag.

SUMMARY OF THE INVENTION Accordingly, an object of the present inventionis to provide an improved gun propellant powder bag.

Another object of the instant invention is to provide a gun propellantpowder bag that resists deformation thus reducing fit interference uponloading in a gun chamber.

A further object of the present invention is to provide a gun propellantpowder bag which is durable and resists ripping, tearing, abrading, rot,and biological degradation.

A still further object of the instant invention is to provide a gunpropellant powder bag that is easy and inexpensive to fabricate.

Still another object of the present invention is to provide a gunpropellant powder bag that has increased electrical conductivity thusreducing the safety hazard of sparking.

A still further object of the instant invention is to provide a gunpropellant powder bag that is compatible with most propellants.

A final object of the present invention is to provide a gun propellantpowder bag that inherently has gun barrel erosion reducing propertiesand is consumable.

Briefly, these and other objects of the present invention are attainedby the use of a powder bag molded or cast of a high density polyurethanefoam in the form of an open-ended cylinder. End caps of consumable clothfabric are adhered to each end after filling. the cylinder withpropellant. One end cap may have attached to'its exterior, a standardignition pad, and attached to this one end on the cylinder, a clothhandling strap. This construction provides a powder bag that iscompletely consumed, and provides barrel erosion reducers in addition toease of manufacture, and durability.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of theinvention and many of the attendant advantages thereto will be readilyappreciated as the same become better understood by reference to thefollowing detailed description when considered in connection with theaccompanying drawing wherein the FIGURE is an isometric view of thenovel gun propellant powder bag.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing, inthe FIGURE, there is shown generally a powder bag 10. Constituting thesides and main portion of the bag is a hollow open cylinder 12 made of arigid high density polyurethane foam, or the like. While this materialis consumable and has inherent gun bore erosion reducing properties,additives may be included, such as conductive carbon and molybdenumdisulfide.

Affixed at one end, as by an adhesive 14, such as a neoprene adhesive isan end cap 16 made of a fabric cloth such as silk or acrylic rayon. Thecylinder 12 is then filled with a propellant 20 having the desiredballistic properties.

The other end of the cylinder 12 is closed with a second end cap 18,made of a cloth such as silk or acrylic rayon, and sealed thereto with aneoprene adhesive 14. A standard ignition pad 22 of black powder or thelike is attached to the exterior of the second end cap 18 by means of aneoprene adhesive 14. For loading and handling convenience, a handlingstrap 24 of a suitable consumable cloth is attached to the cylinder 12at the ignition pad 22 end by means of a neoprene adhesive 14.

In use, the gun propellant powder bag 12 may be handled and stored inthe conventional manner and loaded for firing in standardself-obturating gun systems. It is placed in the gun chamber behind theprojectile with the ignition pad 22 to the rear, the breech closed andthe gun fired. The materials of the novel combination are completelyconsumed and reduce gun bore erosion.

Obviously, numerous modification and variations of the present inventionare possible in light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

I claim:

1. A powder bag for a gun propellant charge comprismg:

a hollow open-ended cylinder composed of high density rigid polyurethanefoam;

a pair of end caps closing each end of said cylinder and made of a clothselected from the group consisting of silks, acrylic rayons, andmixtures thereof; and V ,a conductive carbon impregnated into saidcylinder to reduce electrostatic charge build-up.

2. The powder bag of claim 1 wherein said cylinder is impregnated withmolybdenum disulfide.

3. The powder bag of claim 2 further comprising an ignition pad attachedone of said end caps.

4. Thepowder bag of claim 3 wherein said ignition pad is filled withblack powder.

5. The powder bag of claim 4 further comprising a consumable clothhandling strap attached to said cylinder at the ignition pad end.

6. The powder bag of claim 5 wherein said handling strap, said ignitionpad, and said end caps are secured by means of a neoprene adhesive.

2. The powder bag of claim 1 wherein said cylinder is impregnated withmolybdenum disulfide.
 3. The powder bag of claim 2 further comprising anignition pad attached one of said end caps.
 4. The powder bag of claim 3wherein said ignition pad is filled with black powder.
 5. The powder bagof claim 4 further comprising a consumable cloth handling strap attachedto said cylinder at the ignition pad end.
 6. The powder bag of claim 5wherein said handling strap, said ignition pad, and said end caps aresecured by means of a neoprene adhesive.